WebUI: Allow rejecting a promise that is returned from cr.sendWithPromise().

chrome/test/data/webui/settings/cr_settings_browsertest.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /** @fileoverview Runs the Polymer Settings tests. */
 
 /** @const {string} Path to source root. */
 var ROOT_PATH = '../../../../../';
 
 // Polymer BrowserTest fixture.
@@ skipping 104 matching lines @@
 
 CrSettingsSearchEnginesTest.prototype = {
   __proto__: CrSettingsBrowserTest.prototype,
 
   /** @override */
   browsePreload:
       'chrome://md-settings/search_engines_page/search_engines_page.html',
 
   /** @override */
   extraLibraries: PolymerTest.getLibraries(ROOT_PATH).concat([
-    '../promise_resolver.js',
+    ROOT_PATH + 'ui/webui/resources/js/promise_resolver.js',
     'search_engines_page_test.js',
   ]),
 };
 
 TEST_F('CrSettingsSearchEnginesTest', 'SearchEngines', function() {
   settings_search_engines_page.registerDialogTests();
   settings_search_engines_page.registerSearchEngineEntryTests();
   settings_search_engines_page.registerOmniboxExtensionEntryTests();
   settings_search_engines_page.registerPageTests();
   mocha.run();
 });